Police inaction had made her feel like she was at fault.
When contacted by the Herald, Detective Inspector Karyn Malthus said police would not comment on operational matters.
But Ms Malthus said police had talked to people who had previously been spoken to about allegations.
Constitutional law expert Bill Hodge said the new complaint made action against members of the Roast Busters group "more likely than not".
"It's reasonably likely that they've got enough evidence to make an arrest," he said.
Police would want to get it right and not be seen as bowing to public pressure.
Retired accountant Graham McCready, who brought a private prosecution against John Banks over electoral issues, has said he will consider doing the same over the Roast Busters if police do not take action.
The new complaint comes two days after a series of national protests against rape culture.
Police investigating the Roast Busters group have set up a dedicated phone number, 0800 OP CLOVER, to help with the so-called Operation Clover.
The phone line is staffed by the investigation's inquiry team, all of whom are trained to deal with child protection and adult sexual assault.